$OpenBSD: patch-configure_in,v 1.4 2015/08/18 20:41:29 bluhm Exp $
--- configure.in.orig	Tue Jan 18 21:35:28 2011
+++ configure.in	Mon Oct 13 20:09:28 2014
@@ -60,7 +60,7 @@ if [[ -n "$snprintf" ]]; then
    snprintf="#define NO_SNPRINTF"
 fi
 
-AC_CHECK_HEADERS(algorithm algo.h algo)
+AC_CHECK_HEADERS(algorithm algo)
 
 AC_SUBST(linux_pthread)
 AC_TRY_COMPILE([#define _GNU_SOURCE
@@ -92,6 +92,12 @@ AC_TRY_RUN([#ifndef _LARGEFILE64_SOURCE
 #include <fcntl.h>
 #include <unistd.h>
 #include <stdlib.h>
+
+#define O_LARGEFILE 0
+#define off64_t off_t
+#define lseek64 lseek
+#define creat64 creat
+#define open64  open
 
 int main () {
   int fd;
